Place all greens in sink or a large pot; fill to brim with lukewarm water. Let greens stand 15 minutes.
Carefully remove greens from water without disturbing sandy-silt which has settled to the bottom. Wash leaves under running water; tear leaves into small pieces, removing tough ribs.
Place torn greens, onions, turnips, and tasso or ham in a 10- to 12-quart soup pot; fill to top with water. Add sugar, picante sauce, salt and pepper.
Bring to a boil over medium-high heat; boil 5 minutes. Reduce heat. Barely simmer, stirring occasionally, 3 hours. Taste for seasoning; adjust if necessary. Greens should have lots of liquid left; add more water if necessary. Serve hot.